Peritoneal Dialysis in ICU and PD associated Infections · Usual ICU Cases •Somebody already on...
Transcript of Peritoneal Dialysis in ICU and PD associated Infections · Usual ICU Cases •Somebody already on...
Peritoneal Dialysis in ICUand PD associated Infections
Content Sourced From
• Beyond Basic course lecture, c/o Dr Komala
• Nepean Hospital Policies
• ISPD Guidelines
• Kimberley Aboriginal Medical Services Council
Dialysate fluid bag
Parietal
peritoneum
Visceral
peritoneum
Y connector
Regulator
Collection bag
PD catheter
Dialysate
fluid in
peritoneal
cavity
System
Usual ICU Cases
• Somebody already on PD - new Peritonitis
• Regular PD patient with non-related issue
• Two types
– CAPD: continuous ambulatory peritoneal dialysis
– APD: automated peritoneal dialysis
PD - advantages
• PD
– Low technical & nursing requirements
– Low cost
– Does not require vascular access
– Mode of choice in children and neonates
Contraindications in an ICU patient
• Absence of intact peritoneum
• Multisystem organ failure with septic shock
• Severe life-threatening hyperkalemia
• Pleuro-peritoneal communication
• Severe respiratory failure
– Diaphragmatic splinting
Important Factors
• Peritoneal Permeability
• Peritoneal blood flow– Cardiac output
– Blood pressure
– Splanchnic circulation Surface Area
• Dialysate– Solute Characteristics
– Concentration Gradient
– Temperature
– Total Volume in 24 hrs
• Dwell Time
Peritoneal dialysis membrane
• Peritoneum
• Interstitial matrix
• Capillary endothelium
PD Mechanism
• Diffusion (solutes move across membrane)
• Ultrafiltration (water movement)
• Absorption (lymphatic drainage)
Pore Model
Dialysate dwell time
• time
– solute clearance
0.2
0.4
0.6
0.8
1.0
D/P
X
4 8 12 16
Dwell time (h)
UreaCreatinine
Middle molecules
Dialysate dwell time• time
– solute clearance
– ultrafiltrationIn
trap
eri
ton
eal
vo
lum
e, m
l
Time, min
4.25% Dextrose
1.5% Dextrose
Key points - PD• PD suited to children and in low-resource settings
• PD continued if hemodynamically stable and not critically unwell
• Not suitable for rapid correction of metabolic abnormalities, marked hypercatabolism, severe respiratory failure
• Requires intact peritoneum
• PD patients most likely to present to ICU for the usual problems, namely cardiovascular and septic
Catheter infection
• Exit site infection
– purulent discharge +/- erythema
• Tunnel infection
– erythma, tenderness over subcutaneous pathway
• Oral antibiotics
– if no systemic illness and no peritonitis
– Minimum 2 weeks
PD Peritonitis
1. Symptoms / signs of peritoneal inflammation
• pain, tenderness, guarding, rebound
2. Cloudy peritoneal fluid + WCC > 100 x 106
• Neutrophils >15% abnormal
• Neutrophils >50% strong evidence
3. Bacteria on gram stain or culture
PD Peritonitis
• Incidence 1/9 - 1/53 patient-months
• Estimated mortality 6%
• Routes of Infection– Intraluminal
– Periluminal
– Transmural
– Haematogenous
• (Troidle 2006)
Risk Factors
• Diabetes
• Non caucasian
• Obesity
• Temperate climate
• Depression
Treatment Basics
• IV antibiotics if septic
• IP antibiotics if no signs of systemic sepsis
– More effective than IV antibiotics in this situation
• Intensification of PD regimen
• Intraperitoneal heparin
– to reduce fibrin adhesion
Antibiotics
• IP Treatment (Broad spectrum Gram +ve and –ve)
– Cephazolin, 1.5g IP
– Gentamicin, 80mg IP
– Vancomycin, 30mg/kg (if allergy / MRSA / exit site)
• IV Treatment
– Vancomycin 1g + Gentamicin 80mg
• Prophylaxis
– Nystatin 500,000 units QID (5ml)
• Monitor for Toxicity
Mechanical complications
• Catheter blockage – often due to fibrin clots– 500 units heparin to 1 or 2 bags a day
• Respiratory distress– Consider reducing dwell volume
• Pleural effusion– Stop PD, drain effusion, alternative dialysis and
drug delivery
• Hernia– May need change over to automated PD with low
volume till hernia corrected
Metabolic & Volume Complications
• Hyperglycaemia
– Due to high concentration glucose in dialysate
– Permeability increased rapid diffusion
• Fluid Overload
– Rapid absorption leads to reduced ultrafiltration
– Consider Increased Concentration
• Metabolic Acidosis
– Can choose dialysate with bicarbonate instead of lactate
Metabolic & Volume Complications
• Hypotension / Dehydration
• Hypernatremia
– Monitor fluid status, monitor ultrafiltration
• Hypokalemia
– Adjust potassium in dialysate, oral K supplementation
• Protein Loss - supplementation
Indications for PD catheter removal
• Refractory peritonitis (failure to respond 5d)
• Refractory exit site or tunnel infection
• Fungal peritonitis (Definite)
• Pseudomonal peritonitis (Likely)
• Consider for:– relapsing peritonitis
– mycobacterium peritonitis
– multiple enteric organisms
– Pleural effusion
Key points - PD peritonitis
• ANTIBIOTICS– Intraperitoneal antibiotics
– Systemic antibiotics if septic
– Antifungal Prophylaxis
• Remove PD catheter if refractory or fungal
• Nepean policy outlines management